Method and means for detecting motor rotation

Abstract

Apparatus features a microcontroller configured to: receive signaling containing information about a measured change of a magnetic field created by a magnetic circuit driving a motor; and determine corresponding signaling containing information about the speed of rotation of the motor, based upon the signaling received. The microcontroller provides control signaling containing information to control the operation of the motor, including where the motor control is used to control the flow of fluids from a pump. A Hall Effect Sensor is used to sense the magnetic flux and provide the signaling in the form of a feedback signal for implementing motor control. The motor housing has a slot, the Hall Effect sensor is mounted external the motor housing over the slot, and a ferromagnetic bridge is arranged over the Hall Effect sensor to close the magnetic circuit and cause more flux to go through the Hall Effect sensor.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS[0001]This application claims benefit to provisional patent application Ser. Nos. 62 / 052,865 (911-005.079-1 / / F-FLJ-X0015), filed 19 Sep. 2014; 62 / 073,324 (911-005.080-1 / / F-FLJ-X0016), filed 31 Oct. 2014; and 62 / 114,730 (911-005.081-1 / / F-FLJ-X0017), filed 11 Feb. 2015, which are all incorporated by reference in their entirety.BACKGROUND OF THE INVENTION[0002]1. Field of Invention[0003]The present invention relates to a motor control technique; and more particularly relates to a motor control technique that can be used to control the flow of fluids from a pump.[0004]2. Description of Related Art[0005]There are many devices used to measure the rotation of a motor shaft.[0006]A dynamometer measures the rotation of a motor shaft by mechanically coupling the shaft to a rotation sensor.[0007]An encoder is another device which is mechanically coupled to the motor shaft. An encoder uses a patterned wheel which can contain holes for an optical sensor, ma...

AI Technical Summary

Benefits of technology

The present invention relates to a system for measuring the rotation of an electric motor without the need for external devices mounted on the motor shaft. The system uses a Hall Effect sensor that is mounted internally and protected by the motor housing, which minimizes noise and maximizes signal strength. The Hall Effect sensor measures the magnetic field created by the motor components. The method measures changes in physical properties instead of their absolute value, making it simpler and less susceptible to temperature changes. The system allows for a more constant motor speed and accurate motor rotation reading. The method can be applied regardless of the power application method. The technical effects of the system are cost-effectiveness, space save, and accuracy of motor rotation measurement.

Problems solved by technology

One problem with the known techniques used in the above mentioned devices, is that any device which is mechanically coupled to a motor, as is the case with the dynamometer and encoder, will require work from the motor to provide its motion.

This work will increase the load on the motor.

These external devices add extra cost and complexity to any system in which they are installed.

There are also many situations in which the space requirements of the system preclude the use of any external devices mounted on the motor shaft.

It is sensitive to unwanted electrical noise, is dependent on measurements taken when the applied voltage is drastically changed, and also requires temperature correction due to the temperature dependency of the physical properties the system uses to infer motor rotation.

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